Informational Guide

Does a Dehumidifier Help With Allergies?

If you are an allergy sufferer then you will need relief. Do dehumidifiers help with allergies? Learn how they can be of assistance inside the home.

by Josh M

Allergies at home often come from the environment. Outdoor air pollutants such as pollen make their way into the home and wreak havoc on our sinuses. Another pollutant issue comes from dust, pet dander, mold, mildew, and disinfectant allergens. Does a dehumidifier help with allergies?

Dehumidifiers can help reduce allergy symptoms because they limit mold and mildew growth as well as destroy dust mites.

Seasonal Allergies

One common type of indoor allergy is related to seasonal allergies. Seasonal allergies are allergies that occur during particular seasons, such as in the spring or the fall. Most seasonal allergies are caused by pollens (there are several types).

These pollen particles tend to cause “seasonal allergic rhinitis,” which is essentially an irritated nose. Your nose may feel itchy, runny, or stuffy. Pollen enters the home through air conditioner units, open windows, and simply opening doors to get in and out of your home.

Woman Sneezing Due to Allergy
Pet Allergies

If you have pets and have allergies, there is a great possibility that your pets are contributing to your allergy problem. Both cats and dogs have allergens that are often associated with eye and nose symptoms in their owners.

If you have red eyes, leaking eyes, running nose, or stuffy nose, then you may have a reaction to your pet’s dander. This type of allergy is most common among people who suffer from asthma.

Humidity & Dust Mite Allergies

Another indoor allergy is related to dust mites and humidity. While high humidity levels themselves are not responsible for allergies,

Most Common Allergy Symptoms

These are the most common indoor allergy symptoms that allergy sufferers experience:

  • Stuffy Nose
    A stuffy nose tends to be associated with excess sinus pressure and a tight, congested feeling in the nose. Seasonal allergies are often the cause of a stuffy nose.
  • Dry Cough/ Wheezing
    The dry cough and wheezing symptom is another common allergy symptom. This one tends to be associated with hay fever, pollen, or mold. This can also be associated with pet dander allergies
  • Bloodshot Eyes/ Watery Eyes
    Experiencing bloodshot eyes and watery eyes means that a type of allergen has penetrated the mucous membrane around the eye. This typically means that particles are getting into the eye. This happens a lot with pets who get near their owner’s faces. If you have a pet allergy, try keeping your pet at your shoulders or below the shoulders whenever possible.
  • Sore Throat/ Itchy Throat
    The sore throat or itchy throat often indicates that allergy sufferers need to drink more water, but it also indicates an allergic reaction to seasonal allergies. This tends to happen with pollen, hayfever, and other outdoor allergens that make their way indoors.
  • Breathing Difficulty/Chest Tightness
    If you have breathing difficulty or notice that your chest feels tight, you may be suffering from allergies. This is a common symptom for people with asthma to experience when allergens are present.
  • Rashness/Scaly Skin
    Contact dermatitis often leads to rashes and scaly skin. Many allergens can cause your skin to respond with a rash or scales, such as mold.
  • Headache/ Dizziness
    This is a harder symptom to pinpoint because headaches and dizzy feelings can have many causes. However, this is also an allergy symptom.
  • Chronic Fatigue Tiredness
    If you are chronically tired and always feel fatigued, it may be because of your allergies.

Does a Dehumidifier Help Relieve Allergies?

Stop Mold Growth

Mold grows in moist, humid environments. This is why you will often find mold growing in basements and bathrooms. One of the best ways to stop mold growth is to prevent it from happening in the first place.

A dehumidifier will stop mold growth by limiting the amount of moisture in the air. Creating a drier environment will prevent mold from growing and mold spores from contributing to your allergies.

Eliminate Dust Mites

Dust mites are similar to mold spores in that they thrive in a hot, humid environment. Dust mites are also one of the most common allergens, and many people are allergic to them. Using a dehumidifier will keep them from multiplying.

They also thrive off of dead skin cells, which is why we recommend washing your bedding weekly and regularly exfoliating your skin. We also recommend that you vacuum any carpets, rugs, or other upholstery once a week because dust mites enjoy burying in these furniture pieces as well.

Mite Aceria Anthocoptes Acari

Dehumidify Your Crawl Space For An Allergen-Free Home

Many homes have a crawl space, and if your home has one, nearly half of the air in your home will move through your crawl space.

The air moving through the crawl space, however, is not getting the air conditioning from inside the house or the breeze from outside. This area tends to be hot and humid. It is the perfect place for mold and mildew to grow as well as dust mites.

If you have a crawl space, we highly recommend purchasing a dehumidifier specifically for this area and placing it there permanently to ensure that the area isn’t too moist.

Dehumidifier Types & How They Help Allergies

Refrigerant Dehumidifiers

A refrigerant dehumidifier is a dehumidifier that works like your fridge. This process involves using a fan to bring air into the machine and then cooling it quickly over metal plates. As the moisture condenses, water will drip into the tank.

Refrigerant dehumidifiers are the most popular style but work best in hot climates. If you live in a cooler climate, we recommend a desiccant dehumidifier.

Desiccant Dehumidifiers

A desiccant dehumidifier tends to be the best option for small dehumidifiers. They are quiet machines and highly efficient.

Unfortunately, they are the most expensive option for dehumidifiers. These dehumidifiers are particularly effective at pulling water out of hard materials such as concrete and hardwood. They are an excellent choice for basements.

Whole House Dehumidifiers

Whole-house dehumidifiers come in three types: refrigerant dehumidifiers, desiccant dehumidifiers, and thermo-electric dehumidifiers. All three of these types work well depending on your particular situation.

Thermo-electric dehumidifiers are the most affordable and include small desktop models (rather than the whole house size).

However, refrigerant and desiccant dehumidifiers are generally more powerful. A whole-house dehumidifier is large enough to dehumidify your entire home. These work best long-term but can be expensive to purchase and install.

How to Use Dehumidifiers for Allergy Relief?

Using a dehumidifier is a simple process that everyone can learn. Although the full specifications will depend on the type of dehumidifier you are using, these are the general instructions.

#1 — Purchase the Dehumidifier and Put it Together

The first step towards using your dehumidifier is purchasing it and putting it together. Most dehumidifiers can be assembled within 10-15 minutes and only consist of a few pieces. Refer to your manufacturer’s instructions and assemble.

#2 — Positioning the Dehumidifier

For safety, it is important to pay attention to where you position your dehumidifier in your home. Keep your dehumidifier away from furniture, walls, curtains, and beds so that the air can move freely through the machine.

We recommend placing the machine in the area of your home where the most moisture exists. In many cases, it is a good idea to have a dehumidifier on each floor (basement, downstairs, and living room, upstairs).

#3 — Running the Dehumidifier

Once your dehumidifier has been assembled and positioned in your home, it is time to run the machine. We typically recommend setting your dehumidifier between 35% and 45% humidity. Make sure that you frequently check the tank so that you can empty the water that accumulates.

If there is too much water in the tank, the dehumidifier will shut off and will not run. Most people need to empty their dehumidifier every 1-2 days, depending on the size of the dehumidifier and how long it has been running.

Woman in Blue Sweater Blowing Nose Due to Allergies

People Also Ask (FAQ)

Air purifier vs. dehumidifier – Which is best for allergies?

An air purifier is a better choice for allergy sufferers because it eliminates allergens from the air, and allergens are the primary cause of allergies. However, dehumidifiers are particularly helpful for high humidity homes where there is a risk for mold and mildew. A combination of both is a good idea.

What is better for allergies: dehumidifier or humidifier?

This depends on the type of allergies that you have. A dehumidifier works best for those who are allergic to mold and mildew because it can help limit and destroy these allergens. A humidifier adds moisture back into the air and can help with scratchy, itchy throats and noses (dryness in sinus cavities).

Is humidity good or bad for allergies?

This is a trick question. Too much humidity and too little humidity are both bad for allergies. Your home should be around 35% on the humidity level. If it is too low, we recommend adding a humidifier to your home. If it is too high, we recommend adding a dehumidifier to your home.

What humidity level is best for allergies?

The best humidity level for allergies is between 30% and 50%. We recommend sticking between 35%-45% depending on your specific allergy symptoms.

If you tend to experience a dry, scratchy nose and mouth, you will want higher levels of humidity (45%). If not, we recommend lower levels of humidity (35%) to limit mold and mildew growth.


To help with your indoor allergy symptoms, we recommend purchasing a dehumidifier. If you live in a high humidity environment, this will make a massive difference in the allergen levels within your home. Destroy mold, mildew, and limit reactions to other allergens with your dehumidifier.

Last Updated on July 27, 2021

Josh M

My name is Josh and I am obsessed with the HVAC industry. I created this website to help HVAC techs of all levels get the best out of their heating & cooling systems. I have spent thousands of hours studying air conditioners, heaters and home air products so you can learn & buy with confidence. Learn more about the team here.